Metro Transit says despite increased demand, it'll have to cut 65 bus routes and reduce service on another 86 if state lawmakers let a temporary two-year funding plan expire without authorizing any more money for the agency.

Metro officials warned of up to 17 percent cuts in service in a new report sent Monday to the King County Council. Metro says the overall effects would include more crowded buses, far less services throughout King County, longer, less convenient trips to work and school, and an increase in traffic as thousands would return to their cars.

"Our analysis shows that we should be adding service to meet growing demand, but the sad reality is that - without ongoing and sufficient funding - potentially one-third of our routes are on the chopping block, and another 40 percent of our routes face reductions and revisions," said Metro Transit General Manager Kevin Desmond. "The result would be even more crowded buses, riders left at the curb, or people climbing back into their cars - something that would worsen the region's traffic congestion and hurt the economic engine of the state."

The report says the cuts would begin in Fall 2014 if the state Legislature fails to authorize funding to offset a projected $75 million annual budget gap. A temporary $20-per-vehicle charge that helped avert such cuts expires next year. Metro says financial reserves that helped provide a temporary financial stop-gap, have run out.

In addition to state funding, the agency relies on sales tax revenue for about 60 percent of its operating funds, and revenues have continued to fall far short since the economic downturn began in 2008.

King County has joined with the Sound Cities Association and City of Seattle to lobby the legislature and is asking people to contact lawmakers as well. But time is running out. April 9 is the deadline for committees to take up fiscal bills.